Spark-plug serving also as compression and injection valve for internal-combustion engines



A C. 0. LANDGREBE. sPAIIII PLUG SERVING ALso As coMPnEssIoN AND INJECTION vALvE EUR INTERNAL' 4COMBUSTION ENGINES.

APPLICATION FILED IMY 28, 1917.

Patented Dec. 27, 1921.

/III

UNITED STATES PATENT OFFICE.'

CARL OTT() LANDGREBE, OF DRESDEN-A., GERMANY.

SPARK-PLUG SERVING- A'LSO AS COMPRESSION AND INJECTION VALVE FOR NTER- NAL-COMBUSTION ENGINES.

Application filed May 28,

Specification of Letters Patent.

Patented Dec. 27, 1921.

1917. Serial No. 171,552.

(GRANTED UNDER THE PROVISIONS 0F THE ACT 0F MARGH 3, 1921, 41 STAT. L., 1313.)

To all whom t may concern:

Be it known that l, CARL @Tre Lanos-nnen, a subject ot the King of Prussia, residing at Dresden-A., Saxony, Germany, have invented certain new and useful improvements in Spark-Plugs Serving Also as Compression and Injection Valves for internal-Combustion Engines, of which the following is a specification.

My invention relates to spark-plugs which also serve as compression and injection valves for internal combustion engines, and a primary object is 'to provide an improved device oi the type described in which, in contradistinction to those known heretofore, the lower pointed end ot the valve spindle suitably insulated from the casing is automatically seated upon the sharp-edged seat under the action oie a spring and thereby closes the valve, one of the electrodes being carried by the spindle and the other constituted by the casing oi the valve.

As compared with known spark-plugs or with known compression and injection valves, my improved device has a number of advantages, ot' which the following' may be mentioned. Firstly, the valve is closed automatically by means of a spiral spring which constantly tends to turn the threaded spindle in the required direction. Consequently, mistakes in the operation of the valve cannot occur. Secondly, owing to the end of the spindle heilig formed as a needle valve and being seated on the sharp edges of the seat, a reliable tight closure is effected, and as the seat is located near the spark-gap, the interior of the spark-plug does not heat and it is impossible lfor the insulation to crack. Consequently, the long channels or duct-s which are subject to explosions and are readily fouled in devices of the type in question known heretofore, are obviated in my improved device. Further, the improved device enables benzin, petroleum or the like to be readily injected andthe electrodes to be cleaned thereby, and it is consequntly no longer necessary, as formerly, to screw out the valve-spindle for this purpose. Another advantage is that when the valve is fully open no spark can pass, and, lastly, unintentional changes in the length oi the sparkgap cannot be made.

To these ends, the invention consists in the construction, arrangement and combination ot parts described hereinafter and pointed out in the claim.

One illustrative embodiment of the invention and a modification thereof are represented by way of example in the accompanying drawing, wherein:

Figure l is a vertical section showing one form of the improved device, and

Fig. 2 isa like view ot a modified form.

Referring to Fig. l, the spark-plug constituting also a compression and injection valve can be screwed into the cylinder of an engine by means of the internallythreaded casing a shaped like a nut. A tapered nut b ot the form clearly shown in section in the drawing is screwed into the casing a and holds the insulation c firmly in position against a fitting or conical member d which is thereby also held in position; the members l), c, ai are tlrmly held together by means of a nut e which is screwed on the member l and presses on the ring f of insulation placed on the top of the nut b. The member d has an internal thread, into which is screwed the threaded valve-spindle g, the lower end of which is conical and constitutes the valve-disk which is normally seated on the sharp edge of the opening h in the hottom of the member d and thus etfects a reliable tight closure.

A spiral spring z' is arranged in such a manner at the upper end of the valve-spindle g, that it constantly tends to turn the latter into its closed position.

The lower conical end of the spindle g constituting the valve-disk carries a pin Zr; of Suitable material which forms the one electrode. The other electrode is constituted by the bottom of the casing a which may be notched or provided with radial points, not shown.

The spindle g is provided with a longitudinal bore hole Z and with a transverse hole m connected therewith, the bore Z running out at the top into a funnel 1', through which benzin or the like can be introduced. The electric cable (not shown) is suitably connected to the nut e, or is suitably directly electrically connected to the spindle g, and the current passes down the spindle g to the electrode 7c and jumps in the form of a spa-rk` across the gap to the casing a.

A hand lever s serves for turning` the spindle g and opening thereby the valve.

As the benzin passes the electrodes on its being injected through the channels Z, m when the'spindle g is turned and the valve opened, the spark-gap is cleaned in a very simple manner. Y A Y Inthe modied forni of the device shown in Fig. 2 the funnel 7" is arranged laterally on the casing t in such a manner that the channels Z and mare obviated7 the funnel in this modification being` connected by aduct 'n with a space or chamber o located between the valve-spindle Ag and the member CZ.

VOtherwise the arrangement Iand "inode of operation of this -orin are the saine as those of the device described above with reference to'Fig; `1.

I claim A spark plug including an outer casing 2O provided with an internally threaded openlng forming a valve seat at its lower enf.,

and a central hollow electrode providedl with' a' valve at its lower end adapted to be positioned within said opening7 the valve being 25 adapted to seat upon the rotation of the electrode within the opening by reason of the latters engagement with the screw threads. Y

ln testimony whereof l have hereunto set 30 

